SYNLOGIC, INC. — Director's Dealing 2015

Oct 1, 2015

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: Mirna Therapeutics, Inc. (MIRN)
CIK: 0001527599
Period of Report: 2015-09-30

Reporting Person: POWELL MICHAEL (Director, 10% Owner)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Series C Preferred Stock	$0.00		Common Stock (1244268)		Indirect
Series D Preferred Stock	$0.00		Common Stock (583559)		Indirect
Stock Option (Right to Buy)	$6.45	2025-06-04	Common Stock (6666)		Direct

Footnotes

F1: Each share of Series C and Series D Preferred Stock will automatically convert on a one-to-one basis into Common Stock immediately prior to the consummation of the Issuer's initial public offering.

F2: The securities are immediately convertible.

F3: The expiration date is not relevant to the conversion of these securities.

F4: The shares are held by Sofinnova Venture Partners VIII, L.P. ("SVP VIII"). Sofinnova Management VIII, L.L.C. ("SM VIII") is the general partner of SVP VIII. The individual Managers, or the Managing Members, of SVP VIII are Michael Powell, James Healy, Srinivas Akkaraju and Anand Mehra. The Managers share voting and dispositive power with regard to the shares held directly by SVP VIII. Such persons and entities disclaim beneficial ownership over the shares owned by SVP VIII except to the extent of any pecuniary interest therein.

F5: The option vests with respect to 20% of the shares subject thereto on May 1, 2015, with the remaining shares vesting with respect to 1/8 of the remaining shares subject thereto on each six month anniversary thereafter, subject to the Reporting Person continuing to provide services to the Issuer through each such vesting date.